1. Cut the tomato on a board and then tip it into a bowl. Halve and then destone the avocados, scooping the flesh, along with the tomato.
2. Place all of the ingredients into the bowl and then season with salt and pepper. Whisk or mash everything together to form the guacamole mixture. If serving right away, scatter with coriander and then serve. If saving, cover with cling film and then place in the refrigerator immediately.
3. Serve the vegetable crudites with the guacamole.